AI Face Swap for Videos Explained
AI face swap for videos replaces faces while keeping motion intact. This guide covers models, inputs, outputs, and practical workflows using concrete specs from Flixly tools.
TL;DR
AI face swap for videos replaces a source face with a target face across frames without changing body motion or audio. Models like Seedance 2.0 handle 1920x1080 clips up to 30 seconds at 8 credits. Inputs are a short video and one reference image. Outputs match the original duration and frame rate. Workflows often chain the result into lip sync or reference-to-video extensions.
What AI face swap for videos actually does
AI face swap for videos replaces a source face with a target face across every frame of a clip. It does not create new scenes or alter body movements.
How the models process frames
Seedance 2.0 and Kling 3.0 analyze each frame for facial landmarks then map the target identity onto the source motion. Veo 3.1 adds temporal consistency checks to reduce flicker between frames. Wan 2.7 focuses on lighting match across 24 fps footage.
The process starts with a reference image of the target face at 512 by 512 pixels. The video input runs at 1920 by 1080 resolution and 30 seconds in length. Output clips stay within the same frame count and aspect ratio.
Concrete inputs and outputs
Users upload a 10-second source video and a single reference photo. The system returns a new 10-second clip with the swapped face. Credit cost sits at 8 credits for a 1080p render using Seedance 2.0.
Another workflow takes a 5-second clip at 24 fps and swaps two faces in one pass. The result keeps original audio unless paired with a separate tool.
Typical file specs
- Source video: 1920x1080, MP4, 30 fps
- Reference image: 512x512, PNG
- Output duration: 5 to 30 seconds
- Credit range: 5 to 12 per generation
Real workflows that use face swap
Editors combine face swap with Lip Sync Video when dialogue must match new mouth movements. A 15-second clip processed first through face swap then lip sync keeps both identity and speech sync.
Product teams run face swap inside Video to Video pipelines to test different spokespeople on the same script. One test used a 20-second product demo and swapped three different faces, each at 8 credits.
Creators also feed swapped output into Reference to Video to extend a short clip into a longer sequence while holding the new face.
Comparison of supported models
| Model | Max duration | Frame rate | Credit cost | Strength noted |
|---|---|---|---|---|
| Seedance 2.0 | 30 seconds | 30 fps | 8 | Expression accuracy |
| Kling 3.0 | 20 seconds | 24 fps | 10 | Lighting consistency |
| Veo 3.1 | 15 seconds | 30 fps | 12 | Low flicker |
| Wan 2.7 | 25 seconds | 24 fps | 7 | Fast processing |
Where to start
Open the Image to Video page, upload a short clip and a clear face reference, then run the first generation with Seedance 2.0.
FAQ
Does face swap preserve original audio?
Yes. The audio track stays untouched unless you route the output through a separate lip-sync pass.
What resolution works best for reference photos?
512 by 512 pixels gives the cleanest mapping in current models; lower resolutions increase edge artifacts.
Can I swap multiple faces in one clip?
Current runs support one primary swap per generation. Multiple faces require sequential passes.
How long does a 10-second 1080p swap take?
Seedance 2.0 finishes in roughly 45 seconds; Kling 3.0 averages 60 seconds on the same length.
Is there a limit on source video length?
The platform caps single generations at 30 seconds to maintain quality across frames.
Frequently Asked Questions
Does face swap preserve original audio?▾
Yes. The audio track stays untouched unless you route the output through a separate lip-sync pass.
What resolution works best for reference photos?▾
512 by 512 pixels gives the cleanest mapping in current models; lower resolutions increase edge artifacts.
Can I swap multiple faces in one clip?▾
Current runs support one primary swap per generation. Multiple faces require sequential passes.
How long does a 10-second 1080p swap take?▾
Seedance 2.0 finishes in roughly 45 seconds; Kling 3.0 averages 60 seconds on the same length.
Is there a limit on source video length?▾
The platform caps single generations at 30 seconds to maintain quality across frames.
